What You Should Be Doing NOW to Protect Yourself from Radiation
by George Washington
It is well-known that potassium iodide works to protect against damage from radioactive iodine by saturating our body (the thyroid gland, specifically) with harmless iodine, so that our bodies are unable to absorb radioactive iodine from nuclear accidents.
For example, the World Health Organization notes:
The thyroid gland is at particular risk from irradiation from radioactive iodine because the thyroid uses iodine to produce hormones that regulate the body’s metabolism. The thyroid gland does not differentiate between non-radioactive and radioactive iodine.
When taken at the appropriate dosage and within the correct time interval around exposure to radioactive iodine, KI [i.e. potassium iodide] saturates the thyroid gland with stable (non-radioactive) iodine. As a result, radioactive iodine will not be taken up and stored by the thyroid gland.